1. Field of the Invention
The present invention relates to electrographic apparatus for use as a copying device and more specifically to a novel toner transfer technique as embodied in copying apparatus.
2. Description of the Prior Art
Prior art apparatus for use in electrographic copying devices utilizing magnetic and conductive toner wherein the toner is transferred to plain paper do not produce a high percentage of toner transfer. In the usual and well-known electrostatic transfer process a corona wire or semi-conductive roller provides an electric field for transferring the charged toner particles. However, at high relative humidity the electric field across the paper and toner decays fairly rapidly resulting in poor toner transfer. In addition, electric charges can be transferred to the conductive toner particles and cause the particles to blow around when their charge is reversed.